Various types of electric systems and electronic devices are powered by rechargeable batteries. For example, electric vehicles, power tools, smart phones, tablet devices, digital music players, keyboards, human interface devices, and laptop computers, among many other types of devices are powered by rechargeable batteries. With a growing abundance of such systems and devices, the demand for efficiently charging the batteries used to power these systems and devices continues to grow as well.
In some embodiments, a rechargeable battery may be charged with a constant electric current. For example, the constant current may be supplied through the battery to recharge to the battery. Further, in some embodiments, a constant voltage may be supplied to the battery. For example, a constant voltage across may be applied across the terminals of the battery to recharge the battery.
In some embodiments, a battery may be charged with a constant current and a constant voltage, often referred to as CC-CV charging. In some embodiments, a battery may be charged by CC-CV charging in two different stages. For example, the first stage may involve charging the battery with a constant current and the second stage may involve charging the battery with a constant voltage. In particular, during the first stage, the battery may charge with the constant electric current flowing to the battery. Further, during this first stage, the voltage of the battery increases. Once the voltage reaches a threshold level, the charging operation is switched from charging with the constant current to charging with a constant voltage.